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31.
Elliott AM Gonzales M Hoeffel JC Le Merrer M Maroteaux P Encha-Razavi F Joye N Berchel C Fliegel C Aughton DJ Beaudry-Rodgers K Hasteh F Nerlich AG Wilcox WR Rimoin DL Lachman RS Freisinger P 《American journal of medical genetics》2002,109(2):139-148
Neu-Laxova Syndrome (NLS) is a severe disorder with intrauterine growth retardation, edema, and characteristic face (including microcephaly with receding forehead, protuberant eyes, a flattened nose, deformed ears, cleft palate, and micrognathia). Ichthyosis is often present. Limb anomalies include hypoplastic fingers and syndactyly of fingers and toes. Patients are usually stillborn or die shortly after birth. We report five unrelated patients--four with atypical NLS and one with typical NLS. All five patients were stillbirths. Clinically, the atypical NLS patients showed a large skull; rhizo-, meso-, and acromelia; and hypoplasia of the metacarpals and phalanges. The feet were similarly affected. Radiographically, the atypical patients showed interpediculate narrowing and hypoplastic vertebral bodies. The long bones were stick-like, showing diaphyseal widening that spared the metaphyses and was more pronounced in the lower extremities. The ilia had a half-moon configuration with widening of the sacrosciatic notches. The ischia were vertical and the pubic bone was absent. The typical NLS patient showed microcephaly, normal vertebral body, and long bone ossification, but a pelvic configuration similar to that of the atypical NLS patients. The common and distinguishing clinical and radiographic features are reviewed. Scott et al. [1981: Am J Med Genet 9:165-175] described two patients with NLS with radiographic and clinical findings similar to patients 1-4 reported here. Patients 1-4 of this report lack the typical findings of NLS and likely represent a distinct lethal skeletal dysplasia. 相似文献
32.
Hilger C Bessot JC Hutt N Grigioni F De Blay F Pauli G Hentges F 《The Journal of allergy and clinical immunology》2005,115(3):617-622
BACKGROUND: Anaphylactic reactions caused by bites of the European pigeon tick Argas reflexus are repeatedly reported. This soft-backed tick is a parasite of wild pigeons colonizing urban buildings and houses. Occasionally the ticks can bite human beings, inducing anaphylactic reactions in sensitized patients. OBJECTIVE: Our aim was to characterize the major allergen implicated in a series of anaphylactic reactions caused by Argas bites and to produce the allergen as recombinant protein for diagnostic purposes. METHODS: Protein extracts were prepared from whole A reflexus bodies, and IgE immunoblots were performed with sera from 13 patients who had an anaphylactic reaction with pigeon tick bites. A cDNA expression library was constructed from whole ticks and screened with a polyclonal rabbit antiserum raised against the major allergen. RESULTS: The cDNA coding for the dominant allergen Arg r 1 could be isolated. It encodes a protein belonging to the lipocalin family. Allergenicity of the recombinant Arg r 1 was confirmed by immunoblot, ELISA, and intradermal skin tests. CONCLUSION: The dominant allergen of A reflexus has been isolated and the corresponding cDNA cloned. The recombinant protein, a lipocalin, was expressed in Escherichia coli and was shown to be immunoreactive in vitro and in vivo. Recombinant Arg r 1 was used as a diagnostic tool in a series of anaphylactic reactions caused by pigeon tick bites. 相似文献
33.
Kh. R. Koczorek H. P. Wolff Marie-Luise Beer 《Journal of molecular medicine (Berlin, Germany)》1957,35(10):497-502
Ohne ZusammenfassungMit Unterstützung der Deutschen Forschungsgemeinschaft. 相似文献
34.
dit Faute MA Laurent L Ploton D Poupon MF Jardillier JC Bobichon H 《Clinical & experimental metastasis》2002,19(2):161-168
Growth of human tumor cells as three-dimensional (3D) multicellular spheroids modifies their invasive properties. Here we study the differences in the biological features of MCF-7, a human breast cancer cell line, and its multidrug resistant variant (MDR-MCF-7) cultured as spheroids or as monolayers. Three-dimensional culture decreased the proliferative rate of both cell lines, reduced the drug sensitivity of MCF-7 cells and did not affect the resistance of MDR-MCF-7 cells. Transmission electron microscopic studies and intercellular junctions labeling showed that MCF-7 spheroids had a junctional system involving E-cadherin, tight-junctions and desmosomes. In MDR-MCF-7 cell spheroids, cell cohesion was mostly due to membrane interdigitations. MDR-MCF-7 cells, but not their parental counterpart, displayed a higher invasive potential when cultured as spheroids, as shown in the Boyden chamber assay. 3D-induced invasiveness was correlated with serine protease and plasminogen activator (PA) secretion. MCF-7 cells did not show any tendency to invade, whatever the mode of culture. These results show that 3D-cultures as spheroids distinctively altered structural features of parental and MDR-MCF-7 cells. In MCF-7 cells, 3D-culture increased cell-cell contacts and drug resistance; in MDR-MCF-7 cells, it induced invasive properties. 相似文献
35.
Cebus monkeys of 3 different age groups were trained to perform an automated behavioral task (delayed response), intended to measure recent memory ability. In in initial study, the aged monkeys (18 years and older) exhibit prprogressively greater performance impairments (relative to young monkeys) as they were required to remember the location of a visual stimulus for increasingly longer durations (0 to 20 sec). This deficits replicated previously published results from aged Rhesus monkeys and appeared similar to the primary memory deficits reported in elderly humans and demented patients. In subsequent studies, the effects of three different cholinomimetics were evaluated for their ability to improve the aged monkey's performance on this task. Each monkey was tested under several acute doses of the cholinergic precursor, choline, the anticholinesterase, physostigmine, and the cholinergic muscarinic receptor agonist, arecoline. The results revealed clear differences in the ability of these drugs to improve performance on this task. Choline exerted no apparent effects in the aged monkeys at any dose tested. Physostigmine clearly enhanced performance in certain aged monkeys, but the optimal dose varied dramatically between subjects, replicating previously published results with aged Rhesus monkeys and humans. Arecoline produced clear improvement within a restricted dose range, with little variation in optimal dose between subjects. In addition to demonstrating differences in the effects of different cholinomimetics on memory performance in aged primates, these data also suggest a possible rationale for future investigations. Assuming that each of these drugs primarily affected cholinergic function in the manner conventionally attributed, these data suggest that, within the cholinergic system, the more directly one stimulates the receptor, the more one might expect robust and consistent effects on memory performance in aged subjects. 相似文献
36.
Gene transfer approaches using viruses such human adenovirus (HAdV) may provide an alternative treatment for diseases involving hematopoietic cells. Better understanding of the cellular mechanisms by which the HAdV introduces DNA into these cells should help in vector design. We examined HAdV intracellular delivery in several cell lines including B and T lymphocytes. We demonstrated that HAdV resistance in most B lymphocytes is the result of moderate HAdV uptake. In contrast, high levels of coxsackie and HAdV receptor (hCAR) are expressed on the surface of HSB2 (T cells), allowing efficient binding and uptake but no transgene expression, probably because of deficient endosomolysis and subsequent exocytose. This work demonstrates the existence of hCAR-dependent and -independent endocytic route in hematopoietic cells. Moreover, it precises the intracellular barriers to be overcome by HAdV in such cells to be infectious and gives previous information's to design new vectors for gene transfer. 相似文献
37.
Jean-Claude Brosse Maryvonne Bonnier Gilbert Legeay 《Macromolecular chemistry and physics.》1981,182(12):3457-3465
It was shown that radical polymerization of butadiene in 1-butanol and 2-butanol, initiated by hydrogen peroxide cleaved into two hydroxyl radicals by heat, leads to three types of polymers according to their respective polydispersity. It was found that the formation of these products — oligomers, polymers, and high polymers — can be influenced by modifying the experimental conditions. Thus, it is possible to obtain selectively oligomers free of polymers and polymers free of low molecular weight oligomers. 相似文献
38.
39.
Identification of a novel coronavirus in patients with severe acute respiratory syndrome 总被引:1,自引:0,他引:1
Drosten C Günther S Preiser W van der Werf S Brodt HR Becker S Rabenau H Panning M Kolesnikova L Fouchier RA Berger A Burguière AM Cinatl J Eickmann M Escriou N Grywna K Kramme S Manuguerra JC Müller S Rickerts V Stürmer M Vieth S Klenk HD Osterhaus AD Schmitz H Doerr HW 《The New England journal of medicine》2003,348(20):1967-1976
40.
R. Ammon M. Apostolakis Beer Gross Stutte und Ludwig Heilmeyer 《Journal of molecular medicine (Berlin, Germany)》1966,44(9):531-532
Ohne Zusammenfassung 相似文献